Air Conditioner Repair Checklist
1. AC Won’t Turn On
There can be a couple of explanations why your air conditioning won’t cool: a blown circuit breaker, incorrect thermostat settings, a turned off switch or an overflowing condensate drain pan.

Blown Circuit Breaker
Your air conditioning won’t work when you have an overloaded breaker.
To check if one has blown, find your home’s main electrical panel. You can spot this gray fixture on the wall in the basement, garage or closet.
- Ensure your hands and feet are free of moisture before you check the panel or breakers.
- Find the breaker marked “AC” and make sure it’s in the “on” spot. If it’s overloaded, the breaker will be in the "off" position.
- Firmly transfer the breaker back to the “on” position. If it instantaneously trips again, don’t touch it and call us at 803-265-4208. A breaker that keeps flipping might signal your home has electrical trouble.
Wrong Thermostat Settings
If your thermostat isn’t giving a sign to your system to run, it won’t activate.
The first step is ensuring it’s switched to “cool” and not “heat.” Otherwise your AC may not start running. You could also receive hot air moving from vents because the heater is going instead.
If you rely on a digital thermostat:
- Replace the batteries if the screen is clear. If the screen is presenting scrambled letters, buy a new thermostat.
- Make sure the proper program is displaying. If you can’t alter it, reverse it by lowering the temperature and pressing the “hold” button. This will make your AC start if programming is wrong.
- Test setting the thermostat 5 degrees cooler than the house’s temperature. Your AC won’t cool if the thermostat matches the room’s temperature.
Once your thermostat is set correctly, you should receive cold air promptly.
If you’re using a smart thermostat, including ones made by Nest, Ecobee, Lux, Honeywell or Bosch, check the manufacturer’s website for help. If you still can’t get it to work, reach us at 803-265-4208 for support.
Shut-Off Switch
Your system probably has a shut-down switch by its outside unit. This device is typically in a metal box mounted on your house. If your equipment has recently been maintained, the switch may have inadvertently been turned off.
Clogged Condensate Drain Pan 
Condensate drain pans keep the surplus condensation your equipment removes from the air. This pan can be found either under or inside your furnace or air handler.
When there’s a blockage or backed up drain, water can accumulate and initiate a safety setting to stop your system.
If your pan involves a PVC pipe or drain, you can drain the additional water with a custom pan-cleaning tablet. You can get these tablets at a home improvement or hardware shop.
If your pan includes a pump, locate the float switch. If the lever is “up” and there’s water in the pan, you might have to install a new pump. Call us at 803-265-4208 for help.
2. AC Blows Warm Air
If your system is on but not providing cold air, its airflow could be clogged. Or it may not have enough refrigerant.

Clogged Airflow
Your system’s airflow can be restricted by a plugged air filter or dirty condenser.
How to Put in a New Your Air Filter
A filthy filter can create a lot of issues, such as:
- Lower airflow
- Frosted refrigerant lines or evaporator coil
- Uneven cooling
- Larger cooling costs
- Causing your system to stop working faster
We recommend replacing flat filters every four weeks, and pleated filters every three months.
If you can’t recall when you last replaced your filter, turn off your unit fully and remove the filter. You can find the filter in your furnace or air pump’s blower compartment. It might also be located in a connected filter case or wall-mounted return air grille.
Hold the filter up to the light. If you can’t see any light, you need to replace it.
How to Clean Your AC Unit
Weeds, plants and bushes can block your condensing unit. This could restrict its airflow, lower its energy efficiency and change your comfort. Here’s a way you can get your system running well again.
- Switch off power completely at the breaker or outdoor device.
- Remove yard debris around the equipment. Once you’ve removed all the debris within a two-foot range, you can use a fine-bristled brush or vacuum to gingerly remove dust from the condenser fins. Distorted fins can also hurt capability.
- Use a hose nozzle to carefully remove gunk off the fins from inside the equipment. Don’t get moisture on the fan motor.
- Turn on the power.
Low Refrigerant Levels
When AC units don’t have enough refrigerant, they’ll have difficulty removing heat and humidity from your space.
Here are a few signs that your system is losing refrigerant:
- It takes an extended amount of time to lower the temperature in your residence and you’re constantly decreasing the temperature on the thermostat.
- Air moving through the registers isn’t as cold as it should be.
- You’re hearing hissing or gurgling noises when the AC is on.
- Your evaporator coil is iced over due to having difficulty handling warmth.
Worried your equipment is leaking refrigerant? You need a licensed heating and cooling service expert to repair the leak and refill the right level of refrigerant in your unit. Get in touch with us at 803-265-4208 for help.
3. AC Not Blowing Enough Air
When it seems like you’re not having enough cool air, there’s probably an obstruction or separation somewhere in your AC system.
- The initial stage is looking at your air filter. Buy a new one if it’s soiled.
- Make sure the ductwork is open around your residence.
- If you’re still not receiving sufficient cold air, you should have your ductwork inspected by a pro like Tri City Fuel & Heating Co., Inc.. Your ductwork might need to be serviced or relinked in tricky locations like your attic, basement or crawl space.